The invention relates to a rotary piston compressor with an axial direction of delivery from the top downwards, in particular of screw spindle-type construction, with cooling ducts for the motors, bearings and sensors, through which ducts a cooling fluid flows, and with a cooling device for the pump space.
A known rotary piston compressor (DE 19522559 A1) of this kind has two screw spindles which intermesh and are driven synchronously by motors. Here, the angles of rotation and speeds of rotation of the two screw spindles or rotors are detected by sensors. The motors are synchronized electronically by means of the signals of these sensors. In the case of such rotary piston compressors, there is, on the one hand, the need to cool the motors, bearings and sensors, and they should be cooled to as low temperatures as possible, e.g. 20.degree. C., although, of course, they should not be cooled down to such an extent that condensation forms. The pump space, which is heated up due to the compression of the medium delivered, must likewise be cooled. However, the pump space must be cooled to a higher temperature of, for example, 60.degree. C. to avoid the pumped medium condensing.
In the case of the known rotary piston compressor, the motors, bearings and sensors are cooled by a cooling fluid which flows through cooling ducts. Although the pump space is cooled primarily by internal cooling of the screw spindles, provision has also been made in one embodiment for the casing of the pump space to be cooled. However, the corresponding cooling fluid must be at a higher temperature than the cooling fluid for the motors, bearings and sensors, making it necessary to have two separate cooling circuits. If the rotary piston compressor is to be serviced or repaired, two cooling circuits have to be divided and emptied. The cooling system is therefore complex and requires a considerable amount of work when disassembling the rotary piston compressor.